At first glance, the title hero of Mozart’s opera Idomeneo seems a tragic figure, entrapped by an evil fate. At a moment of mortal danger he makes a vow to sacrifice to Neptune the first person he meets, should he be allowed to return home safely – but that person turns out to be his son, whom he dearly loves. Yet neither Giovanni Battista Varesco’s libretto nor Mozart’s music offers a straightforward interpretation of the tale. This situates them in a tradition going back to antiquity, in which the heroes of yore were subjected to intense criticism, no matter how much they might also be admired.

The oldest traces of Idomeneus, the warrior of the Trojan War, are found in Homer’s Iliad. Idomeneus belongs to the first group of great Greek heroes who besieged the city. As the King of Crete he leads a considerable contingent of 80 ships to war against Troy. He is of advanced age, but like Achilles he is merciless in battle and an expert in the art of man-to-man combat.

For the Greeks, the Iliad and the Odyssey described the foundations of their community and were thus part of a historical continuum in which they also situated their own experiences. Initially, this stance was unproblematical, for when the Iliad was composed it reflected the self-image of the aristocrats before whom its verses were read. When the Iliad and the Odyssey took on their final literary form in the course of the 7th and 6th centuries BC, the Greek world was in the midst of major upheaval. Kingly rule had been replaced by other political forms – sovereignty shared by several aristocrats, or democracy. These changes made kingship obsolete, and rule by a single man was now regarded as ‘tyranny’ in the worst sense of the word.

There was something else, too: as the shape of the state changed and a new political life and self-awareness emerged, citizens felt able to ponder the position of the gods and their role. As early as the 6th century BC, scholars were confidently asserting that the gods were an invention of man, and that the monsters that figured in the old stories were just imaginary constructions. People began to tell their old stories in different ways.

The consequences of Idomeneus’ vow to Neptune, for example, was retold in two quite different versions. In the first, Idomeneus sacrifices his son but is then driven out by the people of Crete, so appalled are they by his barbaric behaviour. In the second, he intends to kill his son but does not do the deed and consequently plague breaks out. As the guilty party, the godless Idomeneus is compelled to leave the island and thus loses his throne.

The first variant was the great interest in the Age of Enlightenment. Here, Idomeneus is a brutal warrior who accepts the necessity of killing his own son in order to maintain his rule. The Cretan people, however, are no longer willing to tolerate such a violent act and so drive out their king. The people have as little fear of Neptune the monstrous macho god as they have sympathy for Idomeneus’ behaviour – which is why he has to lose his throne.

His people expect him to fight against the god’s demand, for they see it as an expression of an outmoded value system. But it is this system that Idomeneus himself still wishes to uphold. This tale reflects a dual process of emancipation – one that frees us from both our bondage to the gods, and the inappropriate self-interests of a ruling class ready and willing to commit the worst atrocities to maintain its position.

Translated by Chris Walton.

This is an extract from Martin Zimmermann's article 'Between Violence and Lies' in The Royal Opera's programme book, available during performances and from the ROH Shop.

Elektrais a reworking of the great Greek tragedy by Sophocles. To mark the return of Charles Edwards’ production to the Royal Opera House we cast an eye over other operas that have been inspired by Classical myths, poetry and plays.

The second of only three Monteverdi operas to have survived, Il ritorno d’Ulisse is based on the conclusion of Homer’s Odyssey. Ulisse (Odysseus) finally returns home from the Trojan War after ten years of wandering. He discovers his faithful wife Penelope besieged by greedy suitors who believe he is dead. Each of the suitors hopes to inherit Ulisse’s wealth and depose his son Telemaco (Telemachus). With the help of the goddess Minerva, Ulisse disposes of the suitors and convinces Penelope of his true identity. Reunited, husband and wife sing a rapturous duet (‘O delle mie fatiche meta dolce e soave’).

Virgil’s epic poem The Aeneid provided the inspiration for this massive opera. Berlioz wrote his own libretto, referring closely to Virgil’s original text. He loved the Aeneid, and knew it intimately – he described Virgil as ‘the first to find a way to my heart and to enflame my growing imagination’. Over four hours in length, Les Troyens covers the sack of Troy and Aeneas’s romantic and ultimately tragic stay in Carthage. Highlights of the score include the Trojans’ procession with the Trojan Horse in Act I, the burning of Troy and the suicide of the Trojan women in Act II, Dido and Aeneas’s rapturous love duet ‘Nuit d’ivresse’ in Act IV and Dido’s heartbreaking suicide aria ‘Je vais mourir’ in Act V. Les Troyens is perhaps the longest opera to be written on a Classical theme.

The Prologue of Richard Strauss’s opera (in its 1916 revised version) opens with a composer preparing for the premiere of his opera about the Cretan princess Ariadne, abandoned by Theseus on the island of Naxos. The Composer sees Ariadne as the ultimate emblem of fidelity and love, and is horrified to discover that his opera will be staged at the same time as a commedia dell’arte piece, ‘The Unfaithful Zerbinetta’. In the second part of the evening, the story of the mythical Ariadne, three nymphs and the god Bacchus collides hilariously with the dancing, bad behaviour and ironic comments of the commedia dell’arte performers. The legend wins out in the end as the commedia dell’arte troupe leave Ariadne and Bacchus to sing their sublime final duet ‘Lag nicht die Welt auf meiner Brust?’

Harrison Birtwistle’s tautly constructed Royal Opera commission is based on the Greek legend of the Minotaur. The Minotaur had the body of a man and the head of a bull, and may have been the son of the god Poseidon. He was imprisoned in a labyrinth in the Palace at Knossos in Crete, where the Athenian hero Theseus killed him with the help of the Minotaur’s half-sister Ariadne. Birtwistle tells the story from the point of view of all three characters. Theseus is coolly heroic, intent on his task. Ariadne longs to escape the island, and expresses her frustration eloquently in her solo scenes, particularly the third scene in Act I, when she re-enacts the conception and birth of the Minotaur. The Minotaur is given a particularly poignant voice and in his solo scenes movingly describes his tragedy: he is neither man nor beast. Birtwistle draws on Greek theatrical traditions in his use of a masked chorus who torment the Minotaur in his labyrinth.

There are countless other examples of operas inspired by Classical myth. Which is your favourite?